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From: russotto@eng.umd.edu (Matthew T. Russotto)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Novice Programmer Question:  Dynamic Memory Allocation under TC
Message-ID: <1989Dec16.185840.7649@eng.umd.edu>
Date: 16 Dec 89 18:58:40 GMT
References: <3427@husc6.harvard.edu> <24770@cup.portal.com> <4196@sbcs.sunysb.edu> <1856@neoucom.UUCP> <4265@sbcs.sunysb.edu>
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Reply-To: russotto@eng.umd.edu (Matthew T. Russotto)
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In article <4265@sbcs.sunysb.edu> vallon@sboslab10.cs.sunysb.edu (Justin Vallon) writes:
>In article <3427@husc6.harvard.edu>, siegel@endor.harvard.edu (Rich
>Siegel) writes:
>> 	This is a common problem when porting C code from systems where
>> sizeof(int) == sizeof(char *), because standard C assumes that a function
>> which is called before it is prototyped (or before its definition is
>> encountered) returns an int as its result. 
>> ...
>> If you don't wish to #include <storage.h>, you can insert a line like
>> 
>> char *malloc();
>
>Isn't the problem also that malloc also accepts a long size?  When I
>started programming in C using toolbox calls, the biggest problem that
>I had was forgetting to #include <MemoryMgr.h>, and Think C would assume
>that Handle NewHandle(long) was actually int NewHandle(int).  The int
>would be passed, but NewHandle needed a long, it took my two bytes, and
>another extra two from just above the parameter, and I kept getting
>out of memory errors (when allocating 20 bytes), and I'd get a NULL
>handle.
unsigned short i;
for (i=0; i < 65534; i++) {
   printf("Without prototypes, C does no type checking on its parameters\n");
}
This applies to all C routines, as well as non-inline ROM calls (implemented
in MacTraps).  The following WILL work:
Handle NewHandle();
main()
{
	DisposHandle(NewHandle(20L));
}
In fact, for the sick and warped, the following will allocate and dispose
of a 20 byte handle also:
Handle NewHandle();
main()
{
	Point p;

	SetPt(&p, 20, 0);
	DisposHandle(NewHandle(p));
}
A prototype is not necessary to make these routines work properly.  What
is necessary is careful attention to the length of the parameter passed.
--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
][, ][+, ///, ///+, //e, //c, IIGS, //c+ --- Any questions?